Of Chimn y Fireplaces. 525 



When the width of the fireplace is reduced, the edges 

 of the covings a A and b B are to make a finish with 

 the front of the jambs. And in general it will be best, 

 not only for the sake of the appearance of the chimney, 

 but for other reasons also, to lower the height of the 

 opening of the fireplace, whenever its width in front is 

 diminished. 



Fig. 4 (Plate IX.) shows a front view of the chimney 

 after it has been altered according to the directions here 

 given. By comparing it with Fig. i (which shows a 

 front view of the same chimney before it was altered), 

 the manner in which the opening of the fireplace in 

 front is diminished may be seen. In Fig. 4, the under 

 part of the doorway by which the chimney-sweeper gets 

 up the chimney is represented by white dotted lines. 

 The doorway is represented closed. 



I shall finish this chapter with some general observa- 

 tions relative to the subject under consideration ; with 

 directions how to proceed where such local circum- 

 stances exist as render modifications of the general plan 

 indispensably necessary. 



Whether a chimney be designed for burning wood 

 upon the hearth, or wood or coals in a grate, the form 

 of the fireplace is, in my opinion, most perfect when 

 the width of the back is equal to the depth of the fireplace, 

 and the opening of the fireplace in front equal to three 

 times the width of the back, or, which is the same thing, 

 to three times the depth of the fireplace. 



But if the chimney be designed for burning wood 

 upon the hearth, upon handirons, or dogs, as they are 

 called, it will sometimes.be necessary to accommodate 

 the width of the back to the length of the wood ; and 

 when this is the case, the covings must be accommodated 



